JP2002348090A - Boom storage device for crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely and easily store a boom after working is finished. SOLUTION: In a crane provided with functions for extending and contracting the boom, for turning up and down the boom for winding up a hook by a winch and for storing the hook, pilot valves 40 for selecting main spools 41 are provided respectively in a selecting control valve 28 for extending and contracting the boom for operating a hydraulic cylinder 8 for extending and contracting the boom, a selecting control valve 29 for turning up and down the boom for operating a hydraulic cylinder 9 for turning up and down the boom, a switching control valve 30 for the winch for operating a hydraulic cylinder 10 for the winch, and there are provided a boom storage indication switch 60, and an arithmetic unit 51 for transmitting a control signal to interlock contraction operations, operarions for turning up and down the boom and operations for winding up the hook with the respective selecting control valves 28, 29, 30 by a prescribed allocation, based on a boom storage indication signal from the indication switch 60.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane boom storage device capable of reliably and easily storing a boom.

[0002]

2. Description of the Related Art In a conventional vehicle-mounted crane, a base is fixed on a chassis frame between a truck bed and a cab, and a column is provided on the base. A boom is provided at an upper end of the column. It is pivoted. The column is turned left and right by a turning hydraulic motor. The boom is extended and retracted by a hydraulic cylinder for extending and retracting the boom, and is raised and lowered by a hydraulic cylinder for raising and lowering the boom. Also, a winch is provided on the column, and a wire rope is guided from the winch to the tip of the boom, and is hooked on the hook via a pulley at the tip of the boom. Hanging. The winch is driven by a winch hydraulic motor to raise and lower the hook.

[0003] In this crane, after the work is completed, the boom is reduced and lowered, the hook is wound up, and fixed at a predetermined storage position with a wire rope or the like, so that the crane has the same running posture as before the start of the work. Recently, as shown in FIG. 4, in a running posture, the hook 73 is stored directly or indirectly in contact with the tip of the boom 77 to prevent the hook 73 from swinging when the truck 76 runs. A crane 71 provided with a hook storage mechanism is also often used.

In the crane 71 provided with such a hook storage mechanism, when the boom 77 is stored and brought into the running posture after the work is completed, the boom 77 is reduced and the boom 7 is moved.
7 is independently performed, and the boom 77 is reduced to the minimum and the boom 77 is tilted down to a predetermined angle. It is common to link the operation with the operation, but this requires a plurality of lever operations and is difficult to operate.

[0005] If the boom 77 is not linked with the hoisting operation for retracting the hook 73, for example, when the boom 77 is first tilted up to the most prone position, the hook operation is performed. 73 is the ground G and the loading bed 7
There is a risk that the wire rope may come loose in contact with 4,
When the hook 73 is wound up in a state where the wire rope is slackened, the wire rope wound around the winch becomes irregularly wound. Also,
When the load W is on the loading platform 74 of the truck 76, the load W
Is hit by the hook 73.

When the operation of storing the hook is performed first,
At the time of the falling operation of the boom 77 to the maximum falling posture, the hook 7
Since the wire rope between the winch 3 and the winch is loosened and moves in the direction in which the hook 73 once stored is released, the storing operation of the hook 73 is required again. Therefore, a crane boom storage device that can more easily perform a boom storage operation has been desired.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem in the operation of storing a crane, and an object of the present invention is to provide a crane boom storage device capable of securely and easily storing the boom after the work is completed. The purpose is to provide.

[0008]

SUMMARY OF THE INVENTION A boom storage device for a crane according to the present invention includes a boom that performs a telescopic operation by a hydraulic cylinder for extending and retracting a boom, and a boom that performs a raising and lowering operation by a hydraulic cylinder for raising and lowering a boom. In a crane provided with a winch performing a hoisting and lowering operation and a hook storage mechanism, a switching control valve for operating a hydraulic cylinder for extending and retracting a boom, a switching control valve for operating a hydraulic cylinder for raising and lowering a boom, and a winch. A winch switching control valve for operating a hydraulic motor for switching, a switching means for switching a main spool thereof is provided, and each of the switching means is controlled based on a boom storage instruction means and a boom storage instruction signal from the boom storage instruction means. Boom reduction operation, boom falling operation and hook hoisting operation By providing the arithmetic unit sends a control signal so as to link with a constant allocation solves the above problems.

[0009] The crane boom storage device of the present invention comprises:
When the boom is stored and the running posture is set after the work is completed, the boom storage instructing means instructs the boom storage. Then, a boom storage instruction signal is sent to the arithmetic unit. The arithmetic unit, based on the boom storage instruction signal, switches the main spools of the boom expansion / contraction switching control valve, the boom raising / lowering switching control valve, and the winch switching control valve,
A control signal is transmitted so that the boom reduction operation, the boom falling operation, and the hook winding operation are linked in a predetermined distribution.

The control signal controls the switching of the main spool between the boom expansion / contraction switching control valve, the boom raising / lowering switching control valve, and the winch switching control valve, and the boom is reduced, the boom is lowered, and the hook is lifted. Since the operation is linked with the predetermined distribution, the boom will shrink the most and fall down the most,
Also, hook storage is performed. As described above, when the boom is retracted to the running posture after the work is completed, it is only necessary to instruct the boom storage by the boom storage instructing means, and it is not necessary to operate a plurality of levers. Becomes

A boom that extends and retracts by a hydraulic cylinder for extending and retracting the boom and performs a raising and lowering operation by a hydraulic cylinder for raising and lowering the boom, a winch that performs a lifting and lowering operation of a hook by a hydraulic motor for a winch, and a hook storage mechanism. In a crane equipped with a boom extension / reduction switching control valve for operating a boom extension / retraction hydraulic cylinder, a boom elevation switching control valve for operating a boom elevation hydraulic cylinder, and a winch switching control valve for operating a winch hydraulic motor, Switching means for switching the main spool are provided, respectively, and a boom storage instructing means, a minimum shrinking and maximum falling down detecting means for detecting a maximum shrinkage and a maximum tilting state of the boom, a boom storing instruction signal and a maximum Each of the switching means based on the detection signal from the reduction and the lodging detection means The provision of the arithmetic unit sends a control signal to actuate the winding operation of the boom reduction operation and the boom lodging actuating the hook in a specified order, by instructing the operating sequence as boom store boom storage instruction means,
The boom reduction operation, the boom falling operation, and the hook winding operation can be performed in any order.

Further, a hydraulic switching means for switching a hydraulic circuit for operating the hydraulic cylinder for extending / retracting the boom, the hydraulic cylinder for raising / lowering the boom, and the hydraulic motor for the winch to a low pressure based on a storage instruction signal from the boom storage instruction means is provided.
When the boom is retracted into the running posture, the boom reduction operation, the boom falling operation, and the hook winding operation are performed at a low pressure, and the boom is stored safely and reliably.

[0013]

FIG. 1 is a front view of a crane provided with a boom storage device according to an embodiment of the present invention, FIG. 2 is a hydraulic circuit diagram of the crane, and FIG. 3 is a configuration diagram of a crane boom storage device. It is. In the crane 1, a column 6 is provided rotatably on a base 4 provided with an outrigger 2, and a boom 7 that expands and contracts is supported on the upper end of the column 6 so as to be able to move up and down. The column 6 is provided with a winch 11, from which the wire rope 12 is connected to the boom 7.
To the tip of the boom 7 (not shown)
The hook 13 is hung from the tip end of the boom 7 by hanging the hook 13 for a load through the hook.

The crane 1 has a column 6 pivoting and a boom 7
The hydraulic motor 5 for turning, the hydraulic cylinder 9 for raising and lowering the boom, the hydraulic cylinder 8 for extending and retracting the boom, and the hydraulic motor 10 for the winch are provided for performing the raising and lowering and expansion and contraction of the winch 11 and the operation of lowering and raising the winch 11. In addition, there are provided outrigger hydraulic cylinders 3L and 3R for performing expansion and contraction operations of the outrigger 2.

The hydraulic motor 5 for turning, the hydraulic cylinder 9 for raising and lowering the boom, the hydraulic cylinder 8 for extending and retracting the boom, the hydraulic motor 10 for the winch, and the hydraulic cylinders 3L and 3L for the outriggers
R is a hydraulic pump 1 driven by the vehicle engine.
It operates by supplying pressure oil from 4 via a switching control valve device 15. The switching control valve device 15 is for controlling each actuator of the hydraulic motor 5 for turning, the hydraulic cylinder 9 for raising and lowering the boom, the hydraulic cylinder 8 for extending and retracting the boom, the hydraulic motor 10 for the winch, and the hydraulic cylinders 3L and 3R for the outriggers. A multi-connection valve device configured by connecting a turning switching control valve 25, a boom raising / lowering switching control valve 29, a boom expansion / contraction switching control valve 28, a winch switching control valve 30, and outrigger switching control valves 23L and 23R. In addition, the device side operation by the operation lever 16 and the remote operation by a remote controller (not shown) are possible.

Further, the switching control valve device 15 is provided with a pressure reducing valve 31, a pressure compensating valve 32, and a relief valve 33 for controlling the internal pressure, and further as a pressure switching means for switching the whole pressure to a low pressure. A low pressure switching solenoid valve 34 and a low pressure relief valve 35 are provided. Note that each of the switching control valves 25, 2 except for the outrigger switching control valves 23L and 23R.
8, 29, and 30 include switching control valves 25, 28, 29,
Each shaft pressure compensating valve 36 is provided to control the flow rate according to the pressure difference between around 30. In addition, each switching control valve 23 except for the lowermost outrigger switching control valve 23L.
R, 25, 28, 29, and 30 are provided with a shuttle valve 37, and each of the actuators 3L, 3R, 5, 8,
At the time of operation of 9, 9, each switching control valve 23L, 23
The operating pressures of R, 25, 28, 29 and 30 are compared, and the maximum pressure is selected by the shuttle valve 37 and supplied to the pressure compensating valve 36 to compensate for the maximum operating pressure and the pressure oil from the hydraulic pump 14. The pressure is made equal by the valve 36 so that an unnecessary pressure is not applied.

As shown in FIG. 3, a main spool 41 is incorporated in the boom expansion / contraction switching control valve 28, the boom raising / lowering switching control valve 29, and the winch switching control valve 30. The spring 43 is normally held at the neutral position. One end of the main spool 41 is connected to the operation lever 16 via a link 45. At the other end, a pilot piston 47 is formed.

A switching control valve 28 for boom expansion and contraction, a switching control valve 29 for boom raising and lowering, and a switching control valve 30 for winch.
Are provided with pilot valves 49 for controlling the main spool 41, respectively.
A control signal is sent from the arithmetic unit 51 to the 0L and 50R via the digital / analog converter 52 and the amplifier 53. The arithmetic unit 51 includes a boom storage instruction switch 60.
Sends a boom storage instruction signal.

The pilot valve 49 has a port E to which pilot pressure oil is supplied from the hydraulic pump 14 normally closed, a port F for returning hydraulic oil to the tank 17 always open, and a control current supplied to the solenoid 50L or 50R. Is input, the left or right pilot spool 54L or 54R slides, and the opening amount of the E port can be controlled by the input current value. Therefore, the left and right oil chambers 47 of the pilot piston 47
The supply of pilot pressure oil to L or 47R is controlled.

When the pilot pressure oil is supplied to one of the oil chambers 47L and 47R, the main spool 41 moves left or right to connect the service ports A and B with the pump port P. Switching control valve 2 for boom expansion and contraction
8, the boom-up / down switching control valve 29 and the winch switching control valve 30 operate the boom extension / retraction hydraulic cylinder 8, the boom-up / down hydraulic cylinder 9, and the winch hydraulic motor 10.

For example, the boom extension / reduction switching control valve 2 shown in FIG.
As shown in FIG. 8, when the main spool 41 moves to the left and the service port A communicates with the pump port P, the hydraulic cylinder 8 for extending and retracting the boom contracts. When the crane 1 is changed from the working posture to the traveling posture after the crane operation is completed, the boom retract switch 60 of the machine side or the remote controller is turned on.
To send a boom storing instruction signal to the arithmetic unit 51. In the arithmetic unit 51, control data for obtaining a required operation limit amount of the main spool 41 is previously stored in order to link the reduction operation of the boom 7, the falling operation of the boom 7 and the winding operation of the hook 13 in a predetermined distribution. The arithmetic unit 51 receives the boom retracting control signal based on the boom storage instruction signal,
A control signal is sent to the boom up / down switching control valve 29 and the winch switching control valve 30 to control the storage operation of the boom 7.

At this time, the control signal from the arithmetic unit 51 causes the boom expansion / contraction switching control valve 28 to operate as the pilot valve 49.
The pilot piston 47 moves to the left by switching
Since the main spool 41 moves to the left and the service port A communicates with the pump port P, the hydraulic cylinder 8 for extending and retracting the boom is contracted and the boom 7 is contracted.
In addition, the boom-up / down switching control valve 29 is also connected to the pilot valve 49.
The pilot piston 47 moves to the left by switching
Since the main spool 41 moves to the left and the service port A communicates with the pump port P, the hydraulic cylinder 9 for raising and lowering the boom is contracted and the boom 7 is lowered.

Further, in the winch switching control valve 30, the pilot piston 47 moves to the left by switching the pilot valve 49, the main spool 41 moves to the left, and the service port A communicates with the pump port P. , The winch hydraulic motor 10 rotates to the winding side and the hook 13
Is carried out. Since the reduction operation of the boom 7, the falling operation of the boom 7, and the winding operation of the hook 13 are linked in a predetermined distribution, the boom 7 falls down at the same time as the most reduction, and the storage of the hook 13 ends.

In the crane boom storage device, a switching signal is sent from the arithmetic unit 51 to the low pressure switching solenoid valve 34 based on a storage instruction signal from the boom storage instruction switch 60, and the entire hydraulic circuit is controlled to a predetermined low pressure. When the boom 7 is retracted to the running position, the operation of reducing the boom 7, the operation of falling down the boom 7 and the operation of winding the hook 13 are performed at a low pressure. Further, the vehicle accelerator opening hydraulic cylinder 61 is stopped to prevent the actuator from operating at a high speed, so that the storage of the boom 7 can be made safe and reliable.

It is not necessary to reduce the pressure of the entire hydraulic circuit when the boom 7 is retracted.
8. Only the switching control valve 29 for boom raising and lowering and the switching control valve 30 for winch may be configured to reduce the pressure. In this case, a relief valve is provided for the boom expansion / contraction switching control valve 28, the boom raising / lowering switching control valve 29, and the winch switching control valve 30, and each of them is operated at an arbitrarily set low pressure.

In general, the operating pressure of the winch hydraulic motor 10 is lower than the operating pressure of the boom extension hydraulic cylinder 8 and the boom raising / lowering hydraulic cylinder 9. Therefore, as an operation start sequence, first, the winch 11 starts the hoisting operation, and thereafter, the boom 7 is contracted and the falling operation is performed. As a result, before the boom 7 is retracted, the hook 13 falls to the ground, the wire rope 12 becomes slack, the winch 11 becomes turbulent, and the hook 13 collides with the luggage loaded on the vehicle bed and damages it. Is prevented.

The hoisting operation of the winch 11 is performed before the boom 7 is contracted or lowered, and the hook 13 is moved to the boom 7.
Even if the boom 7 is in contact with the end of the boom 7 before the end of the boom 7 is reduced, the wire rope 12 and the like are not damaged due to the low pressure, and the boom 7 is reduced while the hook 13 is stored. And the lodging operation is performed. Even when the state of the boom 7 at the start of the storage is the boom minimum contraction, the boom 7 is lowered after the winch 11 is wound up. Even when the state of the boom 7 at the start of the storage is the boom lowest, the winch 11 is wound up. Since the boom 7 is reduced, there is no possibility that the winch 11 will wind up or the hook 13 will collide with the load.

However, when the boom storage instruction switch 60 is turned on when the suspension length L from the end of the boom 7 to the hook 13 at the end of the work is very long, the winch 11
Of the boom 7 is completed before the hoisting is sufficiently performed, and the hook 13 falls on the ground or the bed.
Collision with your luggage can occur.

In order to prevent such a situation from occurring, the winch switching control valve 30 when the winch 11 is wound up.
The amount of movement of the main spool 41 of the boom expansion / contraction switching control valve 28 and the boom up / down switching control valve 29 is reduced with respect to the amount of movement of the main spool 41 of FIG.
The control program of the arithmetic unit 51 can be configured to start the winding of.

Here, the storage of the boom 7 is automatically started by sending a storage instruction signal from the boom storage instruction switch 60 to the arithmetic unit 51. In addition to lowering the pressure of the circuit, the operation order is specified and the boom 7
May be configured to perform the storing operation. In addition, a storage instruction signal is sent from the boom storage instruction switch 60 to the arithmetic unit 51, and a winch operation of the winch 11 is started first by, for example, performing a winch operation of the winch 11 from the operation lever 16 or the remote controller.
Alternatively, the boom 7 may be contracted or the boom 7 may be laid down, so that the boom 7 can be started to be reduced or laid down first.

In this case, a limit switch, a proximity switch, or the like is provided as a detecting means for detecting the state of the boom 7 such as the maximum contraction or the maximum fall, and a signal indicating that the operation of the previous actuator has been completed is sent to the arithmetic operation 51. Then, the operation of the subsequent actuator is started. For example, after the work is completed, the hook 13 is wound up, the winch 11 is wound up from the hook winding stopped state by the hook winding device, the hook 13 is brought into contact with the tip of the boom 7, and then the boom 7 is reduced. Thereafter, when the operator wants to lower the boom 7, the operator turns on the boom storage instruction switch 60, lowers the hydraulic circuit pressure, and starts the hoisting operation of the winch 11.
When the hook 13 comes into contact with the tip of the boom 7, the winch 11 is raised together with the boom 7 and the winch 11 is lifted together with the boom 7 when the boom 7 is reduced. The storage of the hook 13 is ended at the same time as the end of the operation.

The operation sequence can be arbitrarily selected by the operator according to the state at the end of the work.

[0033]

As described above, the boom storage device for a crane according to the present invention can reliably and easily store the boom after the operation is completed.

[Brief description of the drawings]

FIG. 1 is a front view of a crane provided with a boom storage device according to an embodiment of the present invention.

FIG. 2 is a hydraulic circuit diagram of the crane.

FIG. 3 is a configuration diagram of a crane boom storage device. .

FIG. 4 is a side view of a conventional vehicle-mounted crane.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crane 2 Outrigger 4 Base 6 Column 7 Boom 9 Hydraulic cylinder for raising and lowering boom 10 Hydraulic motor for winch 11 Winch 12 Wire rope 13 Hook 14 Hydraulic pump 15 Switching control valve device 16 Operating lever 28 Switching control valve for extending and retracting boom 29 For raising and lowering boom Switching control valve 30 Winch switching control valve 34 Low pressure switching solenoid valve 40 Main spool 47 Pilot pin 49 Pilot valve 51 Arithmetic unit 60 Boom storage instruction switch

Claims (3)

[Claims] 1. A boom, which performs a telescopic operation by a hydraulic cylinder for extending and retracting a boom, and performs a raising / lowering operation by a hydraulic cylinder for raising / lowering a boom, a winch, which performs a lifting / lowering operation of a hook by a hydraulic motor for a winch, and a hook storage mechanism. A crane equipped with a boom extension / retraction switching control valve for operating a boom extension / retraction hydraulic cylinder, a boom elevation switching control valve for operating a boom elevation hydraulic cylinder, and a winch switching control valve for operating a winch hydraulic motor; Switching means for switching the main spool are provided, respectively, and boom storage instructing means, and in accordance with a boom storage instruction signal from the boom storage instructing means, each of the switching means has a boom reducing operation, a boom falling operation, and a hook winding. An arithmetic unit that sends a control signal so that operation Boom storage device of the crane, characterized in that the. 2. A boom, which extends and retracts by a hydraulic cylinder for extending and retracting a boom, and performs a raising and lowering operation by a hydraulic cylinder for raising and lowering a boom, a winch for lifting and lowering a hook by a hydraulic motor for a winch, and a hook storage mechanism. In a crane equipped with a boom extension / retraction switching control valve for operating a boom extension / retraction hydraulic cylinder, a boom elevation switching control valve for operating a boom elevation hydraulic cylinder, and a winch switching control valve for operating a winch hydraulic motor, Switching means for switching the main spool are provided, respectively, and a boom storage instruction means, a minimum reduction and maximum inclination detection means for detecting a maximum reduction and a maximum inclination state of the boom, and a boom storage instruction signal and a maximum value from the boom storage instruction means. Based on the detection signal from the downsizing and top-down detecting means, each of the switching means is blocked. Boom storage device of the crane, characterized in that a an arithmetic unit for sending a control signal to actuate the winding operation of the beam reduction operation and boom lodging actuating the hook in a specified order. 3. A pressure switching means for switching a hydraulic circuit for operating a hydraulic cylinder for extending / retracting a boom, a hydraulic cylinder for raising / lowering a boom, and a hydraulic motor for a winch to a low pressure based on a storage instruction signal from the boom storage instruction means. The crane boom storage device according to claim 1 or 2, wherein: